Hybrid reward-driven reinforcement learning for efficient quantum circuit synthesis

A reinforcement learning (RL) framework is introduced for the efficient synthesis of quantum circuits that generate specified target quantum states from a fixed initial state, addressing a central challenge in both the Noisy Intermediate-Scale Quantum (NISQ) era and future fault-tolerant quantum com...

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Detalles Bibliográficos
Autores: Giordano, Sara, Sen, Kornikar, Martín-Delgado Alcántara, Miguel Ángel
Tipo de recurso: artículo
Fecha de publicación:2026
País:España
Institución:Universidad Complutense de Madrid (UCM)
Repositorio:Docta Complutense
Idioma:inglés
OAI Identifier:oai:docta.ucm.es:20.500.14352/133698
Acceso en línea:https://hdl.handle.net/20.500.14352/133698
Access Level:acceso abierto
Palabra clave:004.27
004.85
530.145
Circuit depth
Circuit optimization
Quantum circuits
Reinforcement learning
Informática (Informática)
Teoría de los quanta
Inteligencia artificial (Informática)
1203.04 Inteligencia Artificial
2212.12 Teoría Cuántica de Campos
1203.02 Lenguajes Algorítmicos
Descripción
Sumario:A reinforcement learning (RL) framework is introduced for the efficient synthesis of quantum circuits that generate specified target quantum states from a fixed initial state, addressing a central challenge in both the Noisy Intermediate-Scale Quantum (NISQ) era and future fault-tolerant quantum computing. The approach utilizes tabular Q-learning, based on action sequences, within a discretized quantum state space, to effectively manage the exponential growth of the space dimension. The framework introduces a hybrid reward mechanism, combining a static, domain-informed reward that guides the agent toward the target state with customizable dynamic penalties that discourage inefficient circuit structures such as gate congestion and redundant state revisits. This is a circuit-aware reward, in contrast to the current trend of works on this topic, which are primarily fidelity-based. By leveraging sparse matrix representations and state-space discretization, the method enables practical navigation of high-dimensional environments while minimizing computational overhead. Benchmarking on graph-state preparation tasks for up to seven qubits, we demonstrate that the algorithm consistently discovers minimal-depth circuits with optimized gate counts. Moreover, extending the framework to a universal gate set still yields low depth circuits, highlighting the algorithm’s robustness and adaptability. The results confirm that this RL-driven approach, with our completely circuit-aware method, efficiently explores the complex quantum state space and synthesizes near-optimal quantum circuits, providing a resource-efficient foundation for quantum circuit optimization.